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Azodicarbonamide (ADA) is approved as a food additive in flour products due to its oxidising and bleaching properties. However, it is prohibited in Australia and Europe on account of its toxicity and the risk of causing asthma in humans. A method was developed to determine ADA in actual flour samples. This work presents an optimised methodology based on derivatisation and clean-up procedures followed by ultra-performance liquid chromatography coupled with electrospray ionisation tandem mass spectrometry (UPLC–ESI-MS/MS). The analytical method was successfully validated. An excellent result was obtained for the linearity of matrix-matched calibration curves (R2 > 0.99) in the concentration range of 0.10–80 mg/kg. The recovery rate varied from 81.7% to 102.3%. The relative standard deviations (RSDs) of repeatability (n = 6) were 1.3–4.1%, and inter-day RSDs (n = 6) were 2.2–4.8%. The limit of detection and the limit of quantification were 0.014 and 0.042 mg/kg, which were significantly lower than the requirement of 45 mg/kg stipulated in the Chinese National Food Safety Standard (GB 2760-2014). The detection rate of ADA in 26 flour samples was 23.1%, with the concentration ranging from 0.023 to 23.2 mg/kg. [ABSTRACT FROM AUTHOR]

The ketamine (KET) and its analogs consumed by humans are becoming emerging contaminants (ECs), as they at present in surface waters after being carried through wastewater systems. Drugs in wastewater can be analyzed using the direct-injection method, a simple wastewater analysis (WWA) method that can provide objective, continuous and nearly to real-time findings. This article describes an ultra-high-pressure liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method for the simultaneous quantification and confirmation of seven KET-based ECs in wastewater by direct injection. After optimization of the UPLC–MS/MS and sample pretreatment conditions, the method was validated and applied to samples (n = 157) collected from several wastewater treatment plants (WWTPs) in southern China in which KET had the highest detection rate. The established direct-injection method was not only simple to perform but also had better sensitivity, shorter detection times, and analyzed more KET-based ECs than currently published methods, meeting the requirements for the monitoring and high-throughput analysis of common KET-based ECs. We also analyzed the fragmentation pathway of KET-based ECs to obtain product ion information on other unknown substances. Additional studies are needed to establish a comprehensive direct-injection screening method of ECs in wastewater on model-based assessment. [ABSTRACT FROM AUTHOR]

An analytical method that combined large-volume solid-phase (Cleanert-PEP) extraction with ultra-performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS) was established for the detection of atrazine, atrazine metabolites, and topramezon residues in environmental water. The results showed that atrazine, its metabolites, and topramezon had a good linear relationship within the linear range of 0.5–50 μg/L, and the linear correlation coefficients of all compounds were r2 ≥ 0.9989. At three spiked levels of 10, 100, and 1000 ng/L, the relative recoveries rate was between 77.1% and 114.1%, with relative standard deviations (RSDs) between 0.9% and 6.8%. The limits of detection (LODs) and limits of quantification (LOQs) of all target compounds were between 0.4 and 3.0 ng/L, and between 1.2 and 10.0 ng/L, respectively. After optimisation, Cleanert-PEP was selected for pretreatment of environmental water, and its elution curve was studied, and the optimal elution volume was 6 mL. The analysis method was applied to surface water bodies around Tai'an City in Shandong Province, China, and none of the target metabolites were detected. This method has the advantages of high sensitivity, good stability, simple operation, and high efficiency. It can be used to quantify topramezon, atrazine, and atrazine metabolite residual in water samples and to investigate their behaviour in environmental water. [ABSTRACT FROM AUTHOR]

To develop a sensitive and fast detection method via ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to assess the concentration of ajuforrestin A, ajuforrestin B, ajugamacrin and 8-O-Acetylharpagide primarily derived from Ajuga plants in mice blood and their pharmacokinetics. Single protein precipitation with high-proportioned acetonitrile is chosen for sample clean-up. The UPLC HSS T3 (2.1 mm × 100 mm, 1.8 µm) column with a mobile phase in gradient elution mode at the flow rate of 0.4 mL/min was used for sample separation. Acetonitrile was selected as the organic phase solution and water containing 0.1% formic acid was chosen as the aqueous solution. A tandem mass spectrometer containing an electrospray ionization (ESI) source in the positive ionization mode was used to detect four compounds via multiple reaction monitoring (MRM). The calibration curves (5–1000 ng/mL) of four compounds were linear with correlation coefficients > 0.997. The matrix effects, accuracy, precision, and recovery were all within permissible scope. In this approach, the corresponding pharmacokinetic parameters were successfully clarified in mouse for the first time, which provided a theoretical basis for the improvement of the standard of Ajuga plants and the safety of clinical medication. Furthermore, this method may provide the UPLC-MS/MS evidence for the differentiation of the main close relative varieties of genus Ajuga according to these plants contain different mixtures of the four marker compounds. [ABSTRACT FROM AUTHOR]

Per- and poly-fluoroalkyl substances (PFAS) are a large group of man-made chemicals that repel oil, stains, grease, and water and are fire resistant. PFAS are known to be persistent in the environment and bioaccumulate in human and animal tissue, soil, and water. To mitigate human exposure to these chemicals, PFAS analysis by ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) was used to monitor their presence in the environment. This study focused on analyzing oysters harvested from coastal New England for 14 PFAS. The validated method addressed in this study utilized a quick, easy, cheap, effective, rugged, and safe (QuEChERS) approach using various sorbents and showed that the combination of primary secondary amine/graphitized carbon black (PSA/GCB) provided the most effective sample clean-up prior to analysis. The recoveries for the targeted analysis ranged from 61% to 116.3% with relative standard deviations from 2.4% to 13.3% at the 125.0 ng mL−1 analyte level. The method detection limits were from 0.33 ng g−1 to 6.75 ng g−1. In a targeted analysis of five unknown samples, two samples had a detectable level of the legacy compound, perfluorooctanesulfonic acid (PFOS). [ABSTRACT FROM AUTHOR]

A method employing online solid phase extraction (SPE) coupled to UPLC-MS/MS was developed for the determination of residues of the acid herbicide quinclorac plus its transformation product, quinclorac methyl ester, in honey. The analytical method involved dissolving the honey in a mixture of methanol:water followed by direct injection into a two-dimensional UPLC system which is used to perform an automated SPE cleanup on a reusable phenyl cartridge prior to the target analytes being transferred onto an analytical UPLC column for subsequent chromatographic separation followed by MS/MS detection. The limits of quantitation for quinclorac and quinclorac methyl ester in honey were both set at 0.5 µg kg−1 and the method detection limit was estimated to be 0.012 µg kg−1 for each compound. The working analytical range (0.5–100 µg kg−1) was validated by analysing a series of spiked replicate honey samples. The method was applied to the analysis of various honeys obtained from numerous different commercial sources. Quinclorac was detected in 9 out of 30 samples at concentrations ranging from 0.6 to 31.5 µg kg−1. Quinclorac methyl ester, which is estimated to be significantly more toxic than the parent herbicide itself, was not detected in any honey sample. [ABSTRACT FROM AUTHOR]

Derazantinib—an orally bioavailable, ATP competitive, multikinase inhibitor—has strong activity against fibroblast growth factor receptors (FGFR)2, FGFR1, and FGFR3 kinases. It has preliminary antitumor activity in patients with unresectable or metastatic FGFR2 fusion-positive intrahepatic cholangiocarcinoma (iCCA). This experiment validates a novel sensitive and rapid method for the determination of derazantinib concentration in rat plasma by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS), and applies it to the study of drug-drug interaction between derazantinib and naringin in vivo. A Xevo TQ-S triple quadrupole tandem mass spectrometer was used for mass spectrometry monitoring in selective reaction monitoring (SRM) mode with transitions of m/z 468 96 → 382.00 for derazantinib and m/z 488.01 → 400.98 for pemigatinib, respectively. The pharmacokinetics of derazantinib (30 mg/kg) was investigated in Sprague-Dawley (SD) rats divided into two groups (with the oral pretreatment of 50 mg/kg naringin or not). The newly optimized UPLC-MS/MS method was suitable for the determination of derazantinib in rat plasma. It was also successfully employed to evaluate the effect of naringin on derazantinib metabolism in rats. After pretreatment with naringin, there was no significant difference in the pharmacokinetic parameters (AUC0→t, AUC0→∞, t1/2, CLz/F, and Cmax) of derazantinib when compared with derazantinib alone. Co-administration of naringin with derazantinib was not associated with significant changes in pharmacokinetic parameters. Thus, this study suggests that the combination of derazantinib with naringin can safely be administered concomitantly without dose adjustment. [ABSTRACT FROM AUTHOR]

Poziotinib and vonoprazan are two drugs mainly metabolized by CYP3A4. However, the drug-drug interaction between them is unknown. To study the interaction mechanism and pharmacokinetics of poziotinib on vonoprazan. In vitro experiments were performed with rat liver microsomes (RLMs) and the contents of vonoprazan and its metabolite were then determined with UPLC-MS/MS after incubation of RLMs with vonoprazan and gradient concentrations of poziotinib. For the in vivo experiment, rats in the poziotinib treated group were given 5 mg/kg poziotinib by gavage once daily for 7 days, and the control group was only given 0.5% CMC-Na. On Day 8, tail venous blood was collected at different time points after the gavage administration of 10 mg/kg vonoprazan, and used for the quantification of vonoprazan and its metabolite. DAS and SPSS software were used for the pharmacokinetic and statistical analyses. In vitro experimental data indicated that poziotinib inhibited the metabolism of vonoprazan (IC50 = 10.6 μM) in a mixed model of noncompetitive and uncompetitive inhibition. The inhibitory constant Ki was 0.574 μM and the binding constant αKi was 2.77 μM. In vivo experiments revealed that the AUC(0-T) (15.05 vs. 90.95 μg/mL·h) and AUC(0-∞) (15.05 vs. 91.99 μg/mL·h) of vonoprazan increased significantly with poziotinib pretreatment. The MRT(0-∞) of vonoprazan increased from 2.29 to 5.51 h, while the CLz/F value decreased from 162.67 to 25.84 L/kg·h after pretreatment with poziotinib. Poziotinib could significantly inhibit the metabolism of vonoprazan and more care may be taken when co-administered in the clinic. [ABSTRACT FROM AUTHOR]

Asini Corii Colla (ACC) and Taurus Corii Colla (TCC) are well-known for their high nutritional value, especially for medicinal purposes. However, the aforementioned are also potential candidates for adulteration because of their low yield and high price. A UPLC-MS/MS approach based on the specific peptide was proposed to detect adulterated gelatin with possible mixed animal species. To explore the antioxidant activity, the peptides were separated to evaluate their effect on ·OH radical and DPPH· scavenging activity, together with PI3K-AKT pathway activation. The results showed that the peptides had excellent DPPH· and ·OH radical scavenging effects, and could alleviate H2O2-induced oxidative stress by promoting the phosphorylation of PI3K and AKT. According to the results of MALDI-TOF/MS, the shared mass-to-charge ratio (m/z) 1466, 1744 and 2382 may serve as a material basis for the antioxidant activity of both ACC and TCC, and contribute to their traditional tonic effects. [ABSTRACT FROM AUTHOR]

Glutathione (GSH) and cysteine are important antioxidants in maintaining the oxidation-reduction balance. 14,15-epoxyeicosatrienoic acid (14,15-EET) and 15-hydroxyeicosatetraenoic acid (15-HETE) are biological active compounds metabolized from arachidonic acid. To dynamically monitor GSH, cysteine, 14,15-EET, and 15-HETE, an ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) method was developed. The derivative GSH, cysteine, and underivatized 14,15-EET, 15-HETE were determined by electrospray ionization source with multiple reaction monitoring. The developed method was well validated and applied to monitor the extracellular concentration of GSH, cysteine, 14,15-EET, and 15-HETE in paraquat (PQ) poisoning LO2 cells. It was shown that the derivation of GSH and cysteine is complete and specific. There was a good linear relationship among GSH, cysteine, 14,15-EET, and 15-HETE. The relative standard deviations of precision and accuracy were all within 15%. After PQ poisoning, the extracellular concentrations of GSH and cysteine were increased at 72 h. 14,15-EET and 15-HETE started to increase at 24 h, earlier than GSH and cysteine. Irreversible pathological alterations appeared at 48 h. In conclusion, a fast and specific UPLC-MS/MS method for the determination of GSH, cysteine, 14,15-EET, and 15-HETE has been developed and validated. PQ induced the increase of 14,15-EET and 15-HETE earlier than that of GSH and cysteine in LO2 cells culture medium. [ABSTRACT FROM AUTHOR]

A new, simple and sensitive method for determining and confirming methylene blue and its analogues such as azure A, azure B, azure C, thionine, and new methylene blue in fish muscles have been developed. The method is based on acetonitrile extraction followed by extract purification using dispersive solid-phase extraction (dSPE) with basic aluminium oxide (ALN) and solid-phase extraction (SPE) using primary and secondary amines (PSA) sorbent in matrix adsorption mode. The separation and detection of the dyes in the fish extract are achieved within 5 min by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) using an octadecyl analytical column with a mixture of acetonitrile, methanol and 0.1% formic acid as a mobile phase in gradient elution. The developed method has been in-house validated according to European law. The method recovery for fish muscle was 98.3–103.1%, whereas the decision limit (CCα) was from 0.45 to 0.49 µg kg−1. [ABSTRACT FROM AUTHOR]

For the simultaneous identification and quantification of five nitrofurans metabolites in farmed shrimp and fish, 3-amino-2-oxazolidinone (AOZ), 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ), 1-aminohydantoine (AHD), semicarbazide (SEM), and 3,5-dinitrosalicylic acid hydrazide (DNSH), an accurate, precise, and specific method was developed. The mixture of water and methanol (60/40; v/v) was found to be the final optimised solvent for injection. The analytical run duration was 7 min, and the mobile phase included 2 mM methanol and ammonium formate. The new reference point for action (RPA) of 0.50 µg kg−1 as per EC/1871/2019 was taken into consideration and evaluated for the performance characteristics as per the CIR (EC)/2021/808 criteria. Specificity, relative retention time (≤0.25%) relative ion ratio (≤40%), linearity (0.25 to 2.0 µg kg−1), trueness (between 82.8 and 118.1%), repeatability (RSDr ≤14%), within lab reproducibility (RSDwr ≤16.9%), CCα (0.32–0.36 μg kg−1), ruggedness and relative matrix effect (≤14.26%) achieved acceptable values. [ABSTRACT FROM AUTHOR]

Context: Aidi injection (ADI), a traditional Chinese medicine antitumor injection, is usually combined with doxorubicin (DOX) for the treatment of malignant tumours. The cardiotoxicity of DOX is ameliorated by ADI in the clinic. However, the relevant mechanism is unknown. Objective: To investigate the effects of ADI on DOX-induced cardiotoxicity and its mechanism. Materials and methods: ICR mice were randomly divided into six groups: control, ADI-L, ADI-H, DOX, DOXþADI-L and DOXþADI-H. DOX (i.p., 0.03mg/10 g) was administered in the presence or absence of ADI (i.p., 0.1 or 0.2 mL/10 g) for two weeks. Heart pathology and levels of AST, LDH, CK, CK-MB and BNP were assessed. H9c2 cells were treated with DOX in the presence or absence of ADI (1, 4, 10%). Cell viability, caspase-3 activity, nuclear morphology, and CBR1 expression were then evaluated. DOX and doxorubicinol (DOXol) concentrations in heart, liver, kidneys, serum, and cells were analysed by UPLC-MS/MS. Results: High-dose ADI significantly reduced DOX-induced pathological changes and the levels of AST, LDH, CK, CK-MB and BNP to normal. Combined treatment with ADI (1, 4, 10%) improved the cell viability, and IC50 increased from 68.51 lM (DOX alone) to 83.47, 176.9, and 310.8 lM, reduced caspase-3 activity by 39.17, 43.96, and 61.82%, respectively. High-dose ADI inhibited the expression of CBR1 protein by 32.3%, reduced DOXol levels in heart, serum and H9c2 cells by 59.8, 72.5 and 48.99%, respectively. Discussion and Conclusions: ADI reduces DOX-induced cardiotoxicity by inhibiting CBR1 expression, which provides a scientific basis for the rational use of ADI. [ABSTRACT FROM AUTHOR]

Platycladus orientalis L. Franco has many folk uses as it is mainly used to treat inflammatory ailments. UPLC–MS/MS was used for the chemical profiling of P. orientalis leaves. Identified metabolites were forwarded to network pharmacology analysis. Networks were constructed based on STITCH, SEA, DAVID, KEGG and STRING databases and using Cytoscape. The identified hit compounds were afzelin, myricetin, apigenin-7-O-hexoside, quercetrin and hyperoside. IL2, VEGFA, AKT1, AKT2, CREB1, IL5, RPS6KB1 and TNF were the main inflammation-related targets identified. Quercetrin and hyperoside were tested for their anti-inflammatory activity. it can be concluded that, the identified hit compounds exhibited strong synergistic interactions with the inflammation and immunity-related targets and pathways. [ABSTRACT FROM AUTHOR]

In this paper, a new hollow fiber liquid-phase microextraction method was developed to improve the extraction of five fluorescent whitening agents that migrated from plastics food contact materials. Influencing factors, such as the types of membrane, the extraction solvent, the stirring speed, the addition of salt ion, and extraction time, were investigated in detail. Under the optimal conditions, high enrichment factors (71–205) can be obtained with 15 μL extraction solvent. The new method is advantageous; the polypropylene hollow fiber membrane modified by sepiolite nanoparticles had excellent solvent binding force and mass transfer effect compared with the conventional extraction technique. The extracts were analyzed by high performance liquid chromatography–tandem mass spectrometry, the limits of detection were 0.3 or 0.9 ng kg−1 with good correlation coefficients (r2 ≥ 0.9940) for the five fluorescent whitening agents. The intra-day and inter-day recoveries ranged between 82.6% and 112%, with a relative standard deviation of less than 12%. The established method was successfully applied to the analysis of fluorescent whitening agent migration from four types of plastic food contact materials immersed in three food simulants. [ABSTRACT FROM AUTHOR]

It is well-established that antibiotics stored individually at their optimal pH and in appropriate solvents are stable over time. However, limited information exists on the stability of antibiotics from multiple classes when prepared and stored as a mixture prior to multiresidue analysis by mass spectrometry. This study tested the stability of antibiotic standard mixtures from eight classes [amphenicols, tetracyclines, sulfonamides, quinolones, macrolides, β-lactams, lincosamides and miscellaneous (i.e., trimethoprim)] in relation to the water:methanol ratio, presence of sodium hydroxide base (to solubilise quinolones), storage temperature, and container type including plain and silanized glass vials. Antibiotics were analysed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry. Several antibiotics, mainly quinolones, tetracyclines and macrolides, were unstable when stored as mixtures for one week regardless of the water:methanol ratio, storage temperature (4, −20 or −80 °C) and presence/absence of sodium hydroxide. Silanization of glassware improved the storage stability of quinolones and macrolides but reduced the stability of tetracyclines and other antibiotics including florfenicol amine, penicillin G, erythromycin and sulfadiazine. Our results show that several antibiotics in water:methanol are unstable when stored as a mixture and suggest a limited advantage of using base or silanized glass vials for the preparation and storage of antibiotic standards mixed together. Freshly prepared antibiotic standard mixtures are recommended for multi-residue quantitation of antibiotics. Abbreviations AMOX: amoxicillin; AMP: ampicillin; AZ: azithromycin; CAP: chloramphenicol; CE: collision energy; CTC: chlortetracycline; CIP: ciprofloxacin; DOX: doxycycline; ENO: enoxacin; ENRO: enrofloxacin; ERYTH: erythromycin; FF: florfenicol; FFA: florfenicol amine; FLU: flumequine; HDPE: high-density polyethylene; LC-MS/MS: liquid chromatography–tandem mass spectrometry; LIN: lincomycin; MRM: multiple reaction monitoring; NOR: norfloxacin; OFL-D3: ofloxacin-D3; OXO: oxolinic acid; OTC: oxytetracycline; PEN-G: penicillin G; PEN-V: penicillin V; ROX: roxithromycin; SDM: sulfadimethoxine; SDZ: sulfadiazine; SMX: sulfamethoxazole; SMZ-D4: sulfamethazine-D4; SSZ: sulfasalazine; TC: tetracycline; TAP: thiamphenicol; TILM: tilmicosin; TRIM: trimethoprim; TL: tolerance limit; VIRG: virginiamycin; UPLC-MS/MS: ultra-high pressure liquid chromatography–tandem mass spectrometry. [ABSTRACT FROM AUTHOR]

Dacomitinib and poziotinib, irreversible ErbB family blockers, are often used for treatment of non-small cell lung cancer (NSCLC) in the clinic. This study investigates the effect of dacomitinib on the pharmacokinetics of poziotinib in rats. Twelve Sprague–Dawley rats were randomly divided into two groups: the test group (20 mg/kg dacomitinib for 14 consecutive days) and the control group (equal amounts of vehicle). Each group was given an oral dose of 10 mg/kg poziotinib 30 min after administration of dacomitinib or vehicle at the end of the 14 day administration. The concentration of poziotinib in plasma was quantified by UPLC-MS/MS. Both in vitro effects of dacomitinib on poziotinib and the mechanism of the observed inhibition were studied in rat liver microsomes and human liver microsomes. When orally administered, dacomitinib increased the AUC, Tmax and decreased CL of poziotinib (p < 0.05). The IC50 values of M1 in RLM, HLM and CYP3A4 were 11.36, 30.49 and 19.57 µM, respectively. The IC50 values of M2 in RLM, HLM and CYP2D6 were 43.69, 0.34 and 0.11 µM, respectively, and dacomitinib inhibited poziotinib by a mixed way in CYP3A4 and CYP2D6. The results of the in vivo experiments were consistent with those of the in vitro experiments. This research demonstrates that a drug–drug interaction between poziotinib and dacomitinib possibly exists when readministered with poziotinib; thus, clinicians should pay attention to the resulting changes in pharmacokinetic parameters and accordingly, adjust the dose of poziotinib in clinical settings. [ABSTRACT FROM AUTHOR]

Honey is a traditional food additive that can be used to preserve food, increase the flavour of food, and enhance the effect of some functional foods. Mulberry leaf is a popular tea, and it is also an anti-diabetic medicinal material. In the traditional processing of mulberry leaf tea, honey is a commonly used additive. This study used ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to measure the changes in the contents of 11 components of mulberry leaves before and after processing using honey as an additive. We analysed the absorption and elimination characteristics of mulberry leaves before and after processing in diabetes in vivo models, and then compared the effect of mulberry leaves before and after processing in resisting hyperglycaemia and hyperlipidaemia damage in in vitro models. The results showed that honey, as an additive, not only improves the dissolution of mulberry leaves, but in diabetes models also increases the utilisation of some components. In an in vitro model, honey mulberry leaves could significantly reduce the apoptosis of vascular endothelial cells. This demonstrated that the traditional processing method using honey as an additive could promote the anti-diabetic effect of mulberry tea. So far, this is the first research report on the quality and role of honey as an additive in mulberry leaf processing. Abbreviations: ML: mulberry leaves; HML: honey mulberry leaves; QC: quality control; HQC: high quality control sample; LLOQ: lower limit of quantification; LQC: low-quality control sample; MQC: medium-quality control sample; MRM: multiple reaction monitoring; STZ: streptozotocin [ABSTRACT FROM AUTHOR]

A UPLC-MS/MS method was developed and validated for the determination of aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2) and ochratoxin A (OTA) in raw coffee samples. Mycotoxins were extracted using a modified QuEChERS method with little sample preparation excluding clean-up and enrichment procedures. Linearity was demonstrated for the five mycotoxins in the range 0.125–20 µg/kg. This method shows negligible matrix effect for individual concentrations, thus allowing the use of an external standard procedure. Limits of quantification (LOQ) ranged from 0.45 to 1 μg/kg. Recoveries between 63% and 89% were achieved. The intra- and inter-day precisions were lower than 15%. The applicability of the method was demonstrated, taking into account fitness for purpose, with simplicity, reliability, low costs and environmental friendliness. The results show that 3 out of 4 samples were contaminated with OTA. [ABSTRACT FROM AUTHOR]

Vitamin D2 is an essential constituent of human nutrition, bone health, and its deficiency can cause various chronic diseases in humans. To meet the daily requirement of vitamin D2, vitamin D2 enrichment in mushrooms like Agaricus bisporus (abundant with pre-vitamin D2) is essential. Once the mushrooms are fortified, their quantification is required to validate the process. So, an analytical method was developed and validated using UPLC-MS/MS. Zorbax Eclipse C18 column was used for vitamin D2 liquid chromatographic separation with mobile phases of methanol, ammonium acetate, and formic acid by gradient elution method. Multiple Reaction Monitoring (MRM) transitions using Electrospray Ionization (ESI) interface was used, and fragmented ion detected was m/z 397/121. The developed method has a Lower Limit of Detection (LOD) of 0.40 ng/mL and covers a wide range of concentrations (0.80–100 ng/mL). UVC light was used to fortify A. bisporus with vitamin D2; optimization was carried out for exposure time and distance. Vitamin D2 from mushrooms was extracted by the Liquid-Liquid extraction method. The maximum increase of 3.2-fold in Vitamin D2 concentration was observed of UV exposure for 1 min and at a distance of 0.35 m. The present study has successfully developed and demonstrated the UPLC-MS/MS method for the quantification of vitamin D2. [ABSTRACT FROM AUTHOR]

The residual elimination of altrenogest in swine was investigated, preparing for the determination of withdrawal time. The residues of altrenogest in sebum, muscle, liver and kidney were extracted by optimized methods and further analyzed by UPLC–MS/MS. Under experimental conditions, the LOD and LOQ of altrenogest in sebum, muscle, liver and kidney were 0.5 and 1.0 μg/kg, respectively. The recoveries were in the range of 65 and 95% and the inter- and intra-RSD were less than 15%. The established method for the extraction, purification and detection of altrenogest is suitable for the determination of the residue of altrenogest in edible tissues of pigs. It was showed that altrenogest had the highest residual concentration level in liver, followed by kidney, sebum and muscle. Then withdrawal time was set at 9 days. The study provides an effective basis for elimination of altrenogest in swine. [ABSTRACT FROM AUTHOR]

The goal of this survey was to evaluate the presence and concentration as well as the co-occurrence of legislated and non-legislated mycotoxins in wheat flour samples from Brazil. A total of 200 wheat flour samples were analysed by a validated multi-mycotoxins method. DON was the mycotoxin with the highest occurrence, being present in 100% of the analysed samples and showing contamination in both years and regions (53–2905 μg kg−1). ZEN was detected in 51% (

Maximum residue limits (MRLs) for pesticides have been established for edible mushrooms in order to control quality and ensure benefits of consumers in numerous countries, especially areas comprising Europe. In this study, by means of optimising extract purification conditions, a high sensitivity and reliability method to simultaneously determine 180 pesticides in mushrooms has been proposed. Matrix effects were minimised by combining QuEChERS extraction and a mixed mode of SPE cleaned up with different adsorbent materials after sample preparation. The method was completely validated following the requirements of SANTE/12682/2019. The LOQs ranged from 2 to 5 μg/kg, well below the MRLs as regulated by the EU (10–50 μg/kg). Both relative standard deviation of repeatability (RSDr) and reproducibility (RSDR) were less than 20% and recoveries varied from 70 to 120%. Therefore, this method was considered to be suitable for routine analysis of multi-pesticide residues in edible mushrooms. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop a rapid and sensitive UPLC–MS/MS approach to determine the sophoridine (SOP) level in rat plasma and the pharmacokinetics of the substance. Sophoridine is used as an anti-inflammatory, anti-virus, anti-microbial, and anti-tumor alkaloid. It is essential to explore specific detection methods for the quantitative analysis of SOP in the blood circulation. The rat plasma samples were prepared by one-step protein precipitation with acetonitrile. Subsequently, the samples were separated by chromatography using a UPLC BEH C18 reversed-phase with an initial mobile phase of methanol and 0.1% formic acid aqueous solution. The gradient elution was performed at a fixed flow rate of 0.4 mL/min, and multiple reaction monitoring (MRM) mode with an electrospray positive ionization source was employed to detect the transitions of m/z 249.1 → 84.2 for SOP and m/z 264.3 → 69.8 for dendrobine (IS). The entire process required 3.5 min for each sample. A linear correlation was established over the range of 2–2000 ng/mL (r2≥0.9954) for SOP in rat plasma with a lower limit of quantification (LLOQ) at 2 ng/mL. The range of accuracy was tested between 94.90% and 100.80%, and the relative standard deviations (RSDs) toward both intra- and inter-day precision were <10%. Thus, this method was successfully applied to a pharmacokinetic study, and the subsequent results demonstrated a low absolute bioavailability of 2.32%. The present study established a reliable method that quantified the SOP concentration in rat plasma after administering a dose of 2 mg/kg intravenously or 20 mg/kg orally. [ABSTRACT FROM AUTHOR]

A number of 344 samples were collected from Tianjin, China and were analysed for the occurrence of emerging Fusarium mycotoxins including enniatin A (ENN A), enniatin A1 (ENN A1), enniatin B (ENN B), enniatin B1 (ENN B1) and beauvericin (BEA) by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The frequencies of mycotoxins studied were 69.0% (40/58), 69.8% (37/53), 85.9% (67/78), 78.9% (75/95), and 30.0% (18/60) for rice, wheat, corn, wheat flour, and corn flour, respectively. BEA was the predominant toxin in rice (average = 37.2 μg/kg) and wheat (average = 58.4 μg/kg), followed by ENN B and ENN B1, while less ENN A and ENN A1 were detected. ENN A was most common in corns with an average level of 28.1 μg/kg, while BEA had a higher average of 62.8 μg/kg. The levels of ENNs and BEA significantly decreased in wheat flours and corn flours, presumably due to the production process. The co-occurrences of ENNs and BEA in cereal samples were common in the combination of two and three mycotoxins and the significant positive correlations in concentrations were also obtained among them. Besides, agroclimate was considered as an important factor for Fusarium production and the mycotoxin contamination was found more serious in Jizhou district, which had more rainfall and less sunshine, than the other agriculture regions. These results suggested the necessity of carrying out in-depth and large-scale monitoring of mycotoxins in cereals and their products nationwide. [ABSTRACT FROM AUTHOR]

A UPLC–MS/MS method was developed and validated the determination and pharmacokinetic study of magnoflorine, cauloside C, hederagenin, and oleanolic acid from Caulophyllum robustum. Digoxin was used as the internal standard. The pretreated plasma samples were carried out on a Waters ACQUITYUPLC HSS T3 column at 35 °C with a mobile phase of acetonitrile–water (90:10, v/v) at a flow rate of 0.2 mL/min. This article describes the most simple, sensitive, and validated UPLC–MS/MS method to date for the simultaneous successful determination of four compounds in rat plasma after oral administration of the extract of C. robustum and their pharmacokinetic studies. [ABSTRACT FROM AUTHOR]

The matrix effect in complex spices and herbs presents a great challenge to the simultaneous, rapid, quantitative analysis of multiple pesticides by mass spectrometry. The aim of this work was to develop and validate an effective UPLC–MS/MS multi-residue method for the analysis of pesticide residues to reduce matrix effects in four spices and one herb and infer which component caused the matrix effect in black pepper. In this paper, we highlight the importance of reducing matrix effects. SPE and dilution factors combined with d-SPE were two approaches to reduce matrix effects compared with d-SPE, and dilution (5-fold) combined with d-SPE was more effective than SPE in reducing matrix effects. With the validated d-SPE method combined with dilution (5-fold), 22 pesticides showed satisfactory recovery (77 to 114%) and RSDs (1.4%–19.1%) at three spiked concentrations in dried chilli pepper, star anise, mint, and cinnamon skin, but not in black pepper. Compared to the other three spices and one herb, black pepper appeared to have a stronger matrix effect. D-SPE method combined with dilution (5-fold) was not suitable for black pepper and required more efficient purification methods and higher dilution factors. With the validated SPE method combined with 10-fold dilution, 19 pesticides showed satisfactory recovery (71% to 113%) and RSDs (2.1%–18.2%) at three spiked concentrations in black pepper. We ascertained that piperine was the component contributing most to the matrix effect in black pepper. The method was used to monitor 15 market samples. [ABSTRACT FROM AUTHOR]

Partial or complete deficiency in the dihydropyrimidine dehydrogenase (DPD) has been observed in 3%–5% and 0.1% of the general population, respectively. It causes severe toxicity in the context of 5-fluorouracil (5-FU) therapy. However, the current tests for determination of DPD deficiency have limitations in routine clinical usage. Therefore, an in vitro approach for simulating 5-FU degradation was established by mixing 5-FU with blank whole blood matrix in this study. The effects of initial 5-FU concentrations and temperatures on DPD activities were investigated as well. The degradation process followed the first-order kinetic reaction (r2 > 0.98). The degradation rates were determined by temperature and individually different. The DPD inhibitor, gimeracil, could block this degradation, which indicated that DPD was the main factor. The degradation process of 5-FU in patients' whole blood in vitro was consistent with it after mixing 5-FU with blank whole blood matrix. In conclusion, mixing 5-FU with blank matrix can simulate the process of 5-FU degradation with DPD. [ABSTRACT FROM AUTHOR]

In this work, broad-specific monoclonal antibody based immunoaffinity columns (IACs) coupled to ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) for purification and determination of T-2 and HT-2 toxin in maize and cherry samples. Based on broad-specific anti-T-2 monoclonal antibody, the prepared IACs could be used for both T-2 and HT-2 purification with cross reactivity values at 100% for T-2 and 108% for HT-2. Column capacity was 3.14 μg mL−1 gel for T-2 toxin, and 3.20 μg mL−1 gel for HT-2 toxin. After 10 cycles of usage at intervals of 2 days, column capacity decreased to 0.85 μg mL−1 gel for T-2 and 1.22 μg mL−1 gel for HT-2 toxin. The developed method exhibited high sensitive results with limit of detection (LOD) lower than 0.35 μg kg−1 and 1.42 μg kg−1. [ABSTRACT FROM AUTHOR]

Rivaroxaban and ticagrelor are two common drugs for the treatment of atrial fibrillation and acute coronary syndrome. However, the drug–drug interaction between them is still unknown. To investigate the effects of ticagrelor on the pharmacokinetics of rivaroxaban in rats both in vivo and in vitro. A sensitive and reliable UPLC-MS/MS method was developed for the determination of rivaroxaban in rat plasma. Ten Sprague-Dawley rats were randomly divided into ticagrelor pre-treated group (10 mg/kg/day for 14 days) and control group. The pharmacokinetics of orally administered rivaroxaban (10 mg/kg, single dose) with or without ticagrelor pre-treatment was investigated with developed UPLC-MS/MS method. Additionally, Sprague-Dawley rat liver microsomes were also used to investigate the drug–drug interaction between these two drugs in vitro. The Cmax (221.34 ± 53.33 vs. 691.18 ± 238.31 ng/mL) and the AUC(0–t) (1060.97 ± 291.21 vs. 3483.03 ± 753.83 μg·h/L) of rivaroxaban increased significantly (p < 0.05) with ticagrelor pre-treatment. The MRT(0–∞) of rivaroxaban increased from 4.41 ± 0.79 to 5.97 ± 1.11 h, while the intrinsic clearance decreased from 9.93 ± 2.55 to 2.89 ± 0.63 L/h/kg (both p < 0.05) after pre-treated with ticagrelor. Enzyme kinetic study indicated that ticagrelor decreased rivaroxaban metabolic clearance with the IC50 value of 14.04 μmol/L. Our in vivo and in vitro results demonstrated that there is a drug–drug interaction between ticagrelor and rivaroxaban in rats. Further studies need to be carried out to verify whether similar interactions truly apply in humans and whether these interactions have clinical significance. [ABSTRACT FROM AUTHOR]

Thirty-nine kinds of antibiotics (11 quinolones, 10 tetracyclines, and 18 sulphonamides) residues were screened in 146 samples including chicken, chicken giblets, and eggs in Fujian by ultra-performance liquid chromatography–tandem mass spectrometry (LC-MS/MS) and analysed the contamination status of antibiotic residues.seventeen kinds of antibiotics were detected, with an overall detection rate of 47.3% and the exceeding rate was 11.6%. Antibiotics were found in 46.7% chicken, 72.2% chicken giblets, and 30% eggs. In 11.1% of chicken giblets and 26% of eggs, the detected concentration exceeded the maximum residue level (MRLs). The total detection rate of tetracycline antibiotics was higher than that of quinolones (33.6% vs. 24.7%) and the sulphonamides (33.6% vs. 4.8%). The exceeding rates of tetracyclines, quinolones, and sulphonamides were 2.7%, 10.3%, and 1.4%, respectively. We suggested that the abuse of antibiotics in poultry foods still exists, and more attention should be paid to the antibiotic residues in poultry eggs. [ABSTRACT FROM AUTHOR]

Semen Cuscutae, which mainly consisted of flavonoids, is a traditional Chinese herbal medicine and used for nourishing the liver and kidneys. The aim of this study was to develop a sensitive and selective UPLC-MS/MS method for simultaneous separation and determination of six main active renoprotective components of Hyperoside, Astragalin, Isoquercitrin, Quercitrin, Quercetin, and Kaempferol from Semen Cuscutae in rat plasma, and to reveal the pharmacokinetic differences between normal and kidney deficient rats. The validated method has been successfully applied to comparing pharmacokinetic profiles of the six analytes in rat plasma. The results indicated that there was significant difference in pharmacokinetic parameters of the six analytes between two groups, while absorptions in kidney deficient group were significantly lower than those in normal group. This study would be helpful for evaluating the Semen Cuscutae as renoprotective drug candidates for pre-clinical and clinical research. [ABSTRACT FROM AUTHOR]

An ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) based multiclass multi-residue method for the simultaneous analysis of 5 polyether ionophores, 4 tetracycline and 10 sulfonamides in animal and aquaculture fish tissues was developed and validated. Sample extraction and clean-up were based on a modified QuEChERS method. The method was validated using an in-house validation based on performance characteristics modified from Commission Decision 2002/657/EC. Both matrix effect and uncertainties associated with sample preparation and instrumental analysis were minimised by the use of matrix-matched calibrations. Recoveries of analytes were generally satisfactory and typically fell between 80% and 113%. The repeatability and intermediate reproducibility measured as relative standard deviations were in most cases less than 15% (n = 63). The decision limit (CCα) and detection capability (CCβ) ranged from 110.7 to 125.8 and 121.5 to 151.7 µg kg−1 for tetracyclines, 113.4 to 118.3 and 116.8 to 126.5 µg kg−1 for sulfonamides and 50.8 to 52.4 and 51.5 to 55.6 µg kg−1 for polyether ionophores, respectively. The method displayed its fitness for purpose through satisfactory results obtained in international proficiency testing schemes. The method was applied to animal and aquaculture fish tissues obtained from different sources in South Africa. Polyether ionophores were predominantly detected in samples in the range 4.26–290.10 µg/kg. Oxytetracycline was found in one porcine liver sample; however, none of the targeted analytes were present above the detection limit in the aquaculture samples. [ABSTRACT FROM AUTHOR]

1. Breast cancer is one of the most common malignancies in women worldwide. Metabolomics has been shown to be a promising strategy to elucidate the underlying pathogenesis of cancer and identify new targets for cancer diagnosis and therapy. Valproic acid (VPA), a histone deacetylase inhibitor, is a potential new drug in tumor therapy. This work used metabolomics to examine the effect of VPA on metabolism in breast cancer cells. 2. Based on UPLC-MS/MS, we identified 3137 differential metabolites in human breast cancer MCF-7 cells and 2472 differential metabolites in human breast cancer MDA-MB-231 cells after VPA treatment. 3. We selected 63 differential metabolites from MCF-7 samples and 61 differential metabolites from MDA-MB-231 cells with the more conspicuous changing trend. Furfural was up-regulated after VPA treatment in both cell lines. In both samples, VPA exerted an effect on the beta-alanine metabolism pathway and the taurine and hypotaurine metabolism pathway. 4. This study identified the effect of VPA on metabolites and metabolic pathways in breast cancer cells, and these findings may contribute to the identification of new targets for breast cancer treatment. [ABSTRACT FROM AUTHOR]

In the present work, the synthesis, characterization, and photocatalytic performance of CuS nanopowder were studied. The achieved photocatalyst was characterized by X-ray diffraction, Scanning Electron Microscopy, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller. The degrading characteristic of CuS photocatalyst was investigated during 100 min and 18 h under visible radiation (Vis irradiation) for degradation of Ofloxacin (OFX), revealing a good degradation rate of OFX. Over 100 min of degradation, some by-products that can be considered as secondary pollutants were produced. Then, to destroy these pollutants the radiation time was increased up to 18 h. The results showed a perfect degradation of OFX and its secondary pollutants. The effective variables including pH, degradation time, and photocatalyst dosage were optimized and studied in multivariate method by design expert7 software. Moreover, the kinetic of the process was evaluated, showing accordance with Langmuir–Hinshelwood model. Recognition of the products was carried out by ultra performance liquid chromatography-tandem mass spectrometer. The synergic effect of CuS adsorbent-photocatalyst exhibited a good adsorption-degradation rate of OFX under Vis irradiation. [ABSTRACT FROM AUTHOR]

Doxorubicin (DOX) is widely used in the chemotherapy of a wide range of cancers. However, intravenous administration of DOX causes toxicity to most major organs which limits its clinical application. DOX-loaded drug delivery system could provide a continuous sustained-release of drugs and enables high drug concentrations at the target site, while reducing systemic toxicity. Additionally, local chemotherapy with DOX may be a promising approach for lowering post-surgical recurrence of cancer. In this study, the sustained-release DOX-loaded implants were prepared by melt-molding method. The implants were characterized with regards to drug content uniformity, micromorphology and drug release profiles. Furthermore, differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) analyses were carried out to investigate the drug-excipient compatibility. To determine the local penetration of DOX in liver, the minipigs received intrahepatic implantation of DOX-loaded implants by abdominal surgery. UPLC-MS/MS method was used to detect the concentration of DOX in liver tissues. Our results suggested that DOX-loaded implants delivered high doses of drug at the implantation site for a prolonged period and provided valuable information for the future clinical applications of the DOX-loaded implants. [ABSTRACT FROM AUTHOR]

Familial adenomatous polyposis (FAP) is an autosomal dominantly inherited intestinal polyposis syndrome accounting for about 1% of colorectal cancers (CRC). Despite increasing researches on the molecular pathogenesis of CRC, we are still unclear about metabolic pathways and alterations probably involved in the development of CRC. To obtain new insights into the mechanisms underlying APC mutation and to elucidate the mechanisms of CRC development, we performed to identify the potential metabolites in FAP based on metabolomic strategy. Serum metabolites from FAP patients (n = 30) and healthy individuals (n = 34) were detected and qualified using Ultra Performance Liquid Chromatography and Tandem Mass Spectrometry (UPLC− MS/MS). 118 metabolites were identified with statistical tests of orthogonal partial least-squares-discriminant analysis (OPLS−DA), with the conditions of variable importance in projection (VIP) >1, p < 0.05 using the Mann−Whitney U test, and fold change (FC) ≥2 or ≤0.5. OPLS-DA model was useful for distinguishing FAP patients from healthy controls. Unique metabolic signatures were pooled in FAP patients covering tricarboxylic acid (TCA) cycle, amino acids metabolism, vitamin D, fatty acids metabolism, and bile acids (BAs) metabolism. Our results demonstrated that metabolites alterations in FAP can be helpful for further analysis of metabonomics induced by APC mutation, and these alterations might be involved in the progress of intestinal carcinogenesis. [ABSTRACT FROM AUTHOR]

The aim of this study was the evaluation of antibacterial and antioxidant properties of Monofloral Etna Castanea sativa Miller honeys. Escherichia coli ATCC 25,922, Pseudomonas aeruginosa ATCC 27,853, Enterococcus faecalis ATCC 29,211 and Staphylococcus aureus ATCC 29,213 were investigated for their susceptibilities to two different honeys. Antioxidant activity was evaluated by ORAC, NO scavenger assays, FRAP and DPPH. Antioxidant activity and antibacterial properties were compared with chestnut honeys from different geographical areas and with Manuka honey. UPLC-MS/MS was used for major components characteri sation. [ABSTRACT FROM AUTHOR]

Rhodamine B (RhB) is a banned food additive and has been classified as illegal colourant. Therefore, the risk of RhB contamination should be strictly monitored. In this study, a sensitive UPLC-MS/MS method was applied to monitor RhB in 292 various spices such as chilli, pepper and tomato products. The results showed 22.7% of chilli powder samples, 18.5% of pepper powder samples, 11.1% of chilli oil samples and 9.1% of pepper oil samples were contaminated with RhB. Chilli powder contained RhB up to 44,935 μg/kg with an average of 743 μg/kg, pepper powder up to 65.9 μg/kg with an average of 4.1 μg/kg, chilli oil up to 14.6 μg/kg with an average of 1.0 μg/kg and pepper oil up to 1.1 μg/kg with an average of 0.2 μg/kg, respectively. Considering the common consumption of chilli products and pepper products by so many consumers, RhB exposure is significant and should be decreased. [ABSTRACT FROM AUTHOR]

Aflatoxin B1 (AFB1) occurrence in peanut oil samples randomly collected from family workshops in western Guangdong during 2016-2017 (n = 427) was surveyed. AFB1 content was screened by enzyme-linked immunosorbent assay (ELISA) protocol and analytically confirmed with an UPLC-MS/MS method. The limit of detection of the ELISA method was 1.08 μg kg−1. The recovery values ranged from 84.4 to 92.6% with relative standard deviations of 2.2 to 4.8%. AFB1 was quantified in 47 samples (22.5%) with a range of 15.4-49.9 μg kg−1 in 2016 and in 33 samples (15.1%) with 8.8-22.2 μg kg−1 in 2017, respectively. The AFB1 contamination in peanut oil was season-depended in western Guangdong with the worst case in spring (24.2-37.9%). Overall, a significant reduction of AFB1 occurrence was observed in western Guangdong after 2016. It is advisable to control AFB1 in bulk and self-pressed oil from family workshops and regulate it mandatorily if necessary. [ABSTRACT FROM AUTHOR]

Our work mainly studied the elimination of zearalenone (ZEN) from corn flour by ozone treatment. We found four degradation products, after separation and identification by UPLC-ESI-QTOF-MS, named as Compound 1 (m/z 335.18), Compound 2 (m/z 351.19), Compound 3 (m/z 321.19) and Compound 4 (m/z 367.18). Then, one main transformation pathway was predicted on the basis of molecular weight and the reaction mechanism of ozone. We had also detected two of the degradation products by our modified UPLC-MS/MS method in real samples—contaminated corn flour. We screened the toxicity of the parent ZEN compound as well as the ozone induced decomposition products with BALB/c mice to evaluate the safety of our method in vivo. Therefore, aqueous ozone was demonstrated to effectively degrade ZEN and chemical structure alternations of ZEN after ozone treatment were predicted in both pure ZEN and real contaminated-corn flour samples. Considering the presence of the by-products formed, differences in the toxic effects on mice exposed to ZEN before and after the ozone treatment emphasise the significance of further study on the quality and toxicity of real food samples after ozone treatment. [ABSTRACT FROM AUTHOR]

1.Mesaconine, an ingredient from Aconitum carmichaelii Debx., has been proven to have cardiac effect. For further development and better pharmacological elucidation, the in vivo process and intestinal absorptive behavior of mesaconine should be investigated comprehensively. 2.An ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the quantitation of mesaconine in rat plasma, tissue homogenates, urine and feces to investigate the in vivo pharmacokinetic profiles, tissue distribution and excretion. The intestinal absorptive behavior of mesaconine was investigated using in vitro everted rat gut sac model. 3.Mesaconine was well distributed in tissues and a mass of unchanged form was detected in feces. It was difficultly absorbed into blood circulatory system after oral administration. The insufficient oral bioavailability of mesaconine may be mainly attributed to its low intestinal permeability due to a lack of lipophilicity. The absorption of mesaconine in rat's intestine is a first-order process with the passive diffusion mechanism. [ABSTRACT FROM AUTHOR]

A new screening method was developed for the simultaneous determination of seven acidic and basic pharmaceuticals by the ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) utilising triple quadrupole mass spectrometry as a detector. The target pharmaceutical compounds of interest in this work belong to different classes of pharmaceutical group with different physico-chemical properties. Both the positive and negative ionisation modes (dual ionisation mode) in electrospray ionisation (ESI) were used simultaneously. Unlike previous studies, the performance of the dual ionisation mode was compared with the positive and negative ionisation modes individually in terms of analysis time and sensitivity. Results indicate that the developed screening method was successfully applied for the simultaneous determination of the acidic and basic pharmaceutical compounds. Using dual ionisation mode reduced the analyses time while still maintaining sensitivity and quality of the analytical result. The new method was implemented in detecting the targeted analyte in a real sample of wastewater. The instrument detection limit (IDL) was as low as 9.7 fg, indicating a high sensitivity as compared to the corresponding methods. The precision of the instrument was calculated as the relative standard deviation (RSD) ranging from 1.4 to 11.0%. The limit of quantification (LOQ) for the method was over the range 0.77-177 ng L−1 and 1.05-100 ng L−1 for the influent and effluent wastewater, respectively. [ABSTRACT FROM AUTHOR]

The determination of acrylamide in potato products, bakery products and coffee, and the human dietary exposure is reported. The method reported is based on a single extraction step with water, followed by the clean-up of the extract using solid phase extraction columns and finally, the determination of acrylamide using UPLC-MS/MS. The MS/MS detection was carried out using an ESI interface in positive ion mode. Internal calibration was used for the quantification of acrylamide, because of the suppression/enhancement matrix effects due to the complex nature of the samples. The method performance characteristics were determined after spiking blank samples. The mean recoveries in spiked coffee samples, potato chips, breakfast cereals and crispbread ranged from 93% to 99%, with RSDs lower than 5% for both repeatability and reproducibility conditions. The estimated limits of detection and quantification of the method were 10 and 32 μg kg−1, respectively. The method was used for monitoring acrylamide in 406 samples. Acrylamide amounts ranged from <32 to 2450 μg kg−1. A total of 360 samples (89%) were contaminated with acrylamide, but only 14% of the samples exceeded the benchmark levels of the EU legislation. Foods with the highest mean acrylamide amounts were potato crisps (642 μg kg−1), French fries (383 μg kg−1) and biscuits (353 μg kg−1). The mean and 95th percentile acrylamide exposures of adolescents in Cyprus were 0.8 and 1.8 μg kg−1 body weight per day, respectively. The estimated levels of dietary exposure to acrylamide are not of concern with respect to neurotoxicity. However, the margins of exposure (MOEs) indicate a concern for carcinogenicity. Potato fried products (45%), fine bakery ware (21%) and potato chips (14%) contributed the most to overall acrylamide exposure. [ABSTRACT FROM AUTHOR]

The 4,4′-methylenedianiline (MDA) substance is an important chemical intermediate which is produced in very large tonnages, the majority of which is consumed in its conversion to 4,4′-methylenediphenyl diisocyanate (MDI). The MDA substance has known adverse effects which can be associated with human and environmental exposure. The growing number and volume of applications of polyurethane formulations containing MDI in the open environment and in agriculture has led to increased concern about indirect exposure to MDA in the environment, where it may occur as a potential degradation product of these polyurethane materials. This method employs ultra performance liquid chromatography coupled to tandem mass spectrometry. A recovery of (101.1 ± 5.2) % of MDA was demonstrated for samples prepared by spiking known amounts of MDA to a representative sandy loam surface soil. The overall method was adjusted to a deliver a dynamic MDA detection range from 5 to 250 μg/kg MDA load (dry wt.) in soils. The accuracy of the method was evaluated at 87%, while intra- and inter-day precision were 9% and 8%, respectively. When coupled with an integrated soil sampling strategy and a solid-liquid extraction protocol validated across a wide variety of soil types, the developed method will prove a powerful tool for definitively quantifying the occurrence (or absence) of MDA in both targeted and exploratory soil monitoring programs. [ABSTRACT FROM AUTHOR]

The genetic potential and biofortification of India-grown rice with bioavailable folate has not been studied yet. The objectives of this study were to determine the folates concentration in four cultivars of rice through UPLC-MS/MS. Total folate concentration in rice cultivars ranged from 11.0 to 51 μg/100 g with a mean of 26.0 μg/100 g. Among the four rice cultivars, the pigmented grain cultivar Nootripathu possesses two-fold rich sources of total folates than the other three non-pigmented grain cultivars. The average value of 100 g serving of rice grains could provide the amount of recommended daily allowance (% RDA) of dietary folates (6.5%) for adults, which ranged from 2.7-12.7%. Among the 5 individual forms of folates, 5-methyltetrahydrofolate was most abundant in rice cultivars followed by 10-Formylfolic acid and folic acid. The result of this study has been useful for biofortification of folates in rice. [ABSTRACT FROM AUTHOR]

A sensitive, rapid and easy analytical method was validated for the determination of quinoid niclosamide (LDS) molluscicide in water, rice and soil using a QuEChERS extraction procedure and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) detection. The LDS was extracted by using acetonitrile and then cleaned up by using dispersive solid-phase extraction with florisil and C18 sorbents. The determination of the target compound was achieved in less than 3 min using an electrospray ionisation source in negative mode. The overall average recoveries for this method in water, rice and soil matrix at three fortified levels ranged from 82.54 to 99.9%, with relative standard deviations in the range of 1.51 to 4.86% (n = 5). The calculated limits of detection were lower than 0.1 µg kg−1 and quantification was 5 µg kg−1; these values were much lower than the maximum residue levels established by the Australian standard (0.01 mg kg−1). The results of the method validation confirmed that this proposed method is convenient and reliable for the determination of LDS molluscicide in water, rice and soil samples. [ABSTRACT FROM AUTHOR]

In the present study, 100 commercial breads and biscuits were investigated for the occurrence of deoxynivalenol (DON) and its acetylated derivatives 3-acetyldeoxynivalenol (3-Ac-DON) and 15-acetyldeoxynivalenol (15-Ac-DON). The target mycotoxins were determined by isotope dilution ultrahigh performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS). DON was determined in 95% of the test samples with a mean value of 153.3 µg/kg. Compared with DON, 3-Ac-DON and 15-Ac-DON were far less frequently detected, with mean values of 1.14 and 0.37 µg/kg, respectively. The estimated daily intakes of the sum of DON and its derivatives in breads and biscuits were 0.0059 and 0.0313 µg/kg bw/day, respectively, which was within the group provisional tolerable daily intake of 1.0 µg/kg bw/day set by the Joint FAO/WHO Expert Committee on Food Additives. In the future, systematic monitoring programmes of DON and its derivatives in relevant foodstuffs are still necessary for food safety and human health. [ABSTRACT FROM AUTHOR]

Systemic absorption of ocularly administered Brimonidine Tartrate has been reported to give rise to several side-effects. Hence, it has become crucial to develop a delivery system that could increase efficacy and reduce systemic absorption. Therefore, the present work aims to develop Brimonidine Tartrate gels with different concentrations (0.05%, 0.1%, and 0.2% w/v, respectively) using Carbopol 974 P and HPMC E4M, and compare the therapeutic efficacy and systemic absorption with that of eye drop (0.2%, w/v) by UPLC-MS/MS. The result of histological analysis did not show any morphological or structural changes after the administration of formulations.In vitroresidence time studies demonstrated that the gels exhibited a better precorneal residence time as compared with the eye drop. The gels with lower concentrations of the drug (0.05% and 0.1%, w/v) could significantly decrease intraocular pressure (IOP) in both normal and water-loaded rabbits as compared to the eye drop. Finally, the values of the ratio of AUC(0→∞)in comparison to eye drop showed the gels with lower concentrations of Brimonidine Tartrate could decrease the systemic absorption. From the result, it can be concluded the 0.1% ophthalmic gel has a potential to improve therapeutic efficacy and reduce the potential toxicity caused by systemic absorption. [ABSTRACT FROM PUBLISHER]

We have developed a rapid, multi-compound analytical method for measuring residues of the pesticides thiamethoxam and its metabolite, clothianidin; fipronil and its three metabolites, fipronil sulfone, fipronil sulfide, and fipronil desulfinyl; and pyraclostrobin in unprocessed foods (rice, corn, cucumbers, tomatoes, apples, and bananas) by ultra-performance liquid chromatography coupled to tandem mass spectrometry. Acetonitrile was used as the extraction solvent, and an octadecylsilane-dispersive SPE was used to clean up the analytes, which were then separated through a UPLC HSS T3 column connected to a tandem mass spectrometer via an electrospray ionisation source. The linearity of this method for the target analytes was excellent (R2 ≥0.990) in the concentration range of 5–1000 μg kg–1. The average recoveries of the seven compounds at concentrations of 10, 100, and 1000 μg kg–1from six spiked matrix samples ranged from 73.6 to 110.6%, all with RSD values of ≤19.7%. The limit of quantification was 10 μg kg–1. The method validated the effectiveness of the method for routine monitoring the residue of these pesticides and their metabolites in foods. [ABSTRACT FROM PUBLISHER]